He’s correct. He specified “ultimately” and “in the very long run”.
Sure, if two players of equal skill play one hand (as the ultimate short term example), one will have to be a winner, and one will have to be a loser, but that’s clearly not what he was talking about.
But for that matter, even as-is, with players of disparate skill levels playing, very few players are winners. The rake is such a huge factor (that very few people actually understand) that 90%+ of players are long term losers, even players who would be good enough to turn a profit in an unraked game. So if you took out the skill differences, the rake would make it 100% very quickly.
Yes. Recreational players tend to not notice even the most obvious things like that, but skilled players will have no problem avoiding losing money to you in the future with such a strategy. It works if there are enough oblivious players - which is why it’s a viable beginner’s strategy at low limits, but that sort of style will just slowly bleed you dry at tougher (generally higher stakes) games.
This is an amusing, but common attitude. If other people are playing that way, that’s awesome. Playing good poker isn’t about imposing your will and beating people in the particular way that strokes your ego - it’s about adjusting to exploit the mistakes that other people make.
“I can’t bluff them! They’ll call me down with anything!”
“And… you think this is a bad thing?”
“Yes! Those idiots clearly don’t know enough to play real poker!”
The proper strategy, here, of course, is not to try to bluff harder and lose, but simply adjust. If they’re going to always call you down, then bet for value and never bluff. You’ll make tons of money off them.
To the OP: you want a simple answer for a subject that’s pretty complex. If you want to get a good understanding of the basics of poker, read “The Theory of Poker” by David Sklansky.